Investments and Fair Value Measurements (Details) - USD ($) $ in Millions	Jul. 02, 2016	Jun. 27, 2015
Available-For-Sale Investments
Amortized Cost/ Carrying Cost	$ 410.0	$ 496.6
Gross Unrealized Gains	109.5	0.1
Gross Unrealized Losses	(0.4)	(0.3)
Available-for-sale Securities	519.1	496.4
Cash equivalents
Available-For-Sale Investments
Available-for-sale Securities	36.1	33.7
Short-term investments
Available-For-Sale Investments
Available-for-sale Securities	311.1	461.9
Other non-current assets
Available-For-Sale Investments
Available-for-sale Securities	0.6	0.8
Debt securities
Available-For-Sale Investments
Amortized Cost/ Carrying Cost	347.9
Gross Unrealized Gains	0.3
Gross Unrealized Losses	(0.4)
Available-for-sale Securities	347.8
U.S. treasuries
Available-For-Sale Investments
Amortized Cost/ Carrying Cost	46.1	51.9
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	0.0	0.0
Available-for-sale Securities	46.1	51.9
U.S. agencies
Available-For-Sale Investments
Amortized Cost/ Carrying Cost	24.9	96.0
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	0.0	0.0
Available-for-sale Securities	24.9	96.0
Municipal bonds and sovereign debt instruments
Available-For-Sale Investments
Amortized Cost/ Carrying Cost	2.0	4.0
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	0.0	0.0
Available-for-sale Securities	2.0	4.0
Asset-backed securities
Available-For-Sale Investments
Amortized Cost/ Carrying Cost	50.4	70.6
Gross Unrealized Gains	0.1	0.0
Gross Unrealized Losses	(0.3)	(0.2)
Available-for-sale Securities	50.2	70.4
Corporate securities
Available-For-Sale Investments
Amortized Cost/ Carrying Cost	224.5	274.1
Gross Unrealized Gains	0.2	0.1
Gross Unrealized Losses	(0.1)	(0.1)
Available-for-sale Securities	224.6	$ 274.1
Marketable equity investments
Available-For-Sale Investments
Amortized Cost/ Carrying Cost	62.1
Gross Unrealized Gains	109.2
Gross Unrealized Losses	0.0
Available-for-sale Securities	171.3
Marketable equity investments \| Short-term investments
Available-For-Sale Investments
Available-for-sale Securities	$ 171.3

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
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-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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